WTF?

OK, clearly, I'm an idiot. I could probably figure this out on my own, but my precious spare time can be so much better spent doing something else, and I know at least one of you on my list knows how to do this.

How the fuck do I run defrag in XP????

I find the defrag.exe files, and they pop up a DOS window for about a second, which goes away. I look under scheduled tasks, and it's not even listed. I thought it was a fluke of my computer, but my boss' computer is the same.

Help! Pretend I'm a total n00b and don't have a clue. And I'd love a path to the program. Please don't tell me anything that begins with "click on the start button", 'cause one of the first things I do on any new system is remove half those things.

Thanks in advance.